Stunted growth in children, a prominent sign of malnutrition, is often associated with stunted economic growth. Today, the problem is largely confined to low-income countries. One long-standing anomaly, however, is that India, despite having a higher GDP per capita than over 60 countries, ranks fifth in stunting. Public health experts have attributed this anomaly to poor sanitation, which can lead to intestinal diseases, and, in turn, to stunting even with adequate diet and care. New research suggests a somewhat more complex picture. For cultural and religious reasons, Hindu families generally value the health of their first son over that of their other children, and the pattern of stunting strongly reflects these preferences. First sons are above average height, but additional sons and daughters show the effects of poor care and nutrition. The impact of social norms can be seen by regional contrasts in India itself. In the state of Kerala, which has much greater levels of gender equality, this disparity between children does not appear. Thus, while development and redistribution remain vital, such public health problems will go unresolved without a focus on social norms as well. To achieve greater health and equity, social and economic transformation must go hand-in-hand.